Composite control surface for airplanes



April 5, 1932. J BLONDlN 1,852,199

COMPOSITE CONTROL SURFACE FOR AIRPLANES Filed Jan. 13, 1950 INVENTQR,

Z1 TTORNEY Jae 0% 32077012 Patented Apr. 5, 1932 :rosnrn BLONDIN, or Los nnennns, CALIFORNIA ooivirosrrn oonrnon SURFACE non. AIRPLANES Application filed January 13, 1930. Serial No; 420,540.

My instant invention relates to airplanes which employ wing braces of the inclined strut type, and to a method and means for improving the control of such airplanes, in all attitudes of pitch, roll and yaw, and whereby said means also function as an air-brake to overcome the momentum of the machine as a whole, when landing; hence the terms universal and composite function as applied to this invention. a

All conventional airplanes employ a hinged, horizontal surface or elevator to control pitch attitudes: two hinged, horizontal surfaces or ailerons to control roll attitudes,

and a hinged vertical surface or rudder to control yaw attitudes, and no practical airbrake mechanism has yet been developed, to my knowledge. r

My present invention, in the form of a pair of simple surface elements, is intended to supplement the functions of all ofthe separate control elements enumerated above, as

well as to provide in a practical form, a braking mechanism for airplanes.

This universal or composite functionv control means comes propitiouslyat a time when airplanes are being constructed in ever-increasing dimensions. This extensionof airplane dimensions involves a corresponding extension ofitheir center of inertia which introduces an artificial or false moment of stabilityexists. gusts, etc.) disturbs this false stability,'the air planes extended center of inertia opposes re-establishment of real stability much more than in the case of smaller machines whose center of inertia is made to coincide more closely withtheir true center of gravity.

Present day,'tri-motored airplanes carrying wing-engine nacelles and loads, and disposing their passenger loads far to the rear of themachines center of gravity, and future,

'P Q ger airplane designs now under H construction in which eng ne and passenger false, because it exists only while it a When 1 any extraneous force (air loads will be disposed along and within the wing element, are notable cases wherein the machines center of inertia becomes a menace,

instead of a contribution, to the real stability of the ship. The ships in question therefore reach a point in dimensions where their elevator, aileron and rudder surfaces become inadequate because they are forced to act upon a moment-arm measured to the ships center of inertia instead of its center of gravity, 5 and some added means of intensifying the action of said control surfaces or of supplementing their action becomes necessary in the interest of maneuverability and safety. a

It is an object of this invention to provide an auxiliary means to supplement the action of the conventional control elements of airplanes. This means becomes particularly practical in all types of airplanes whose wing I element is braced by inclined struts" extending between said element and theairplane7s fuselage. This invention employs a desired length of the rear set of such struts to serve as posts to which are hinged control surfaces similar to the machines ailerons and disposed, 70 likethe ailerons, one ateach side of the inachine. Unlike the ailerons, however, these auxiliary control surfaces are disposed to operate independently of each other and upwardly only, being stopped against operation below the plane of the" respective strut to which each quasi-aileron surface is hinged. 1

These auxiliary control surfaces are operated in suitable -manner, as by the pilots feet throughthe medium of a split or divided rud- 30 der-bar and appropriate control. cables. 1

This same rudder-bar also operates the usual rudder as in conventional types except that the cables operating the, rudder are attached thereto by a yielding means, such as a set of tension springs. Thus, operating right rudder-bar will turn the rudder-surface to the right and will simultaneously lift the right dihedral, universal or composite function control surface above the plane of the I DO right-hand rear strut at which position it will mally lends no assistance towards proper 1 banking of the machine for the turn.

ing all this operation of right turn andleft; universal control surface is inoperative and surfaces b Durlying in the bed of the wind directly in the plane of the'strut to which it is hinged. As

a corollary, stepping on leftrudder bar Will operate the left rudder and left universal control simultaneously, while the right unlversal control surface remalns inoperative.

Thus these universal control surfaces become effective and practical auxiliary or supplementary rudders.

Should the airplane as a Wholelose lateral stability, rolling toward the right, and requiring aileron, action for recovery, the right aileron would be lowered as in conventional practice and the left aileron would be raised. 1 In such case the pilot would operate the left universal control'surface Which would 7 rise' and thus supplement the action of the left aileronand simultaneously, also, the left rudder would be operated, all these maneuvers co-operating to bring the machine to an even keel and thus j these universal, control iary and supplemental ailerons.

With this invention, upon landing thepilot would instinctively push his feet" forward (just as' an automobile driver does to release clutch and set brakes) and, 'ithrough the me.-

dium of the two-part rudder bar, both universalcontrol surfaces would be made to lift in action simultaneously, introducing a positive brakingeffect: against the air and supple- 'ment such. other mechanical medium as might be employed. Thus, these universal control surfaces become efiective and ,pracv ticalauxlllary brakes. Durlng this braking oper'atlon the machlnes conventional rudder would remain inactive because of the. give "of the provided springs under'the pull,

rearward of the machines center of gravity,

equally, ofthe rudder cables. 7 Further, since these universal controls are hinged to the rear set of wing strutsflvhich are normally located their dra g'and downward components of air pressure would supplement the action ofthe rear elevator in holding the machines tailskid 7 down in contact with, the ground. WVherefore, the universal control surfaces become effective and" practical," auxiliary elevators.

ecome effective and practical, auxil- A special object is, therefore, to provide,- in one control element, auxiliary efforts supplementing the actions of all of the control elements normally used on conventional type airplanes; together with the provision of an entirely new brake function designedto facilitate and shorten the length of run of the airplane on the ground when landing.

vT he invention consists of certain advancements in this art as set forth in the enclosing disclosure and having, with the above, additional objects and advantages, and whose construction, combination and details of means, and the manner of operation will be 7 7 made manifest-in the description of the herewith illustrative apparatus; it being understood that modifications,- variations and adaptations may be resorted to within the scope, principleland spirit of the invention as it is more directly claimed hereinafter.

Figure 1 is'a bottom plan of, an "airplane showing the location of the universal control surfaces.

Figure 2 is a front elevation showing the universal control surfaces in elevated positlon for conpmct ve tClllQILtO serve as a1r-' brakes.

Figur 3 SllOWS in detail thedivided rudder-bar mechanism and the control cables employed to operate the composite function surfaces. 7 c

The assembly includes a conventional type monoplane with a fuselage-A, wings B, tail ;G, fin D elevator E and rudder F, ailerons G andG, running gear H, and dihedral struts I andI, and J and'J Hinged to the latter are the two universal or composite-function control surfaces K and K whichare designed to operateupWard only, as shown in Fig. 2,

being restrained from any movement. below the'plane of the respective s respective "rests L'and L. f

I 3 illustrates; the independent rudderbar arms M and M- which operate the vertical rudder F, through the medium of the cable tensioningfispr-ings'o and" O: WVhenthe rudder bars are operated inlconjunction these springs permit the concurrent give of the cables and N without afiectingitheangui 'lar position of the rudder propers c When one rudder bar, as arm M, 'isfloperated alone the rudder 'propermwill' be actuated "by the cable N,: not. positively, as in conventrutsd and tlfb r tional practice, but yieldingly 'again'st'ithe 7 v tension ofthessprings O and 0, while at' the same timefthe cable P'will' serve topull up 7 the controlsurface K which is thus made co operative by its drag and banking elfectswith the rudder F, in steering the airplanefto; the

right. 7 During this op fationl the rudder bar arm M remains inactive, neutral position,

and therefore control ;surface K: remains 'eat d'e it res shes o LIT S il 1y, when right joystick is operated to bank the airplane to the right through the medi um of the conventional ailreons G and G right rudder bar M would be operated to effect the action of the universal control surface K and this would co-operate with the aileron G in banking the airplane to the right, aided simultaneously by the drag of surface K and the turning couple introduced by the rudder F, to steer the airplane as a whole to the right.

What is claimed is:

1. In airplane controls, auxiliary independent control surfaces hinged to conventional inclined struts as carrier parts and which are each provided with an independent rudder bar member, and a rudder actuated by either member.

2. In airplane controls, a right hand and a left hand supplemented aileron surface for braking function in flight by air resistance and hinged to relative dihedral wing struts and operated independently, by transmission means in conjunction with and auxiliary to the action of the usual rudder surfaces.

3. An airplane having, in combination, a steering rudder, and a system of air brake surfaces co-operatively combined with the rudder, and means for operating either brake surface and the rudder irrespective of the other surface, said means having only an upward positive action on said surfaces.

4. An airplane having, in combination, a steering rudder, a pair of air resistance braking surfaces to reduce speed of ship before and after landing and operating means connecting the said surfaces andthe rudder and positively moving said surfaces in one direction only.

5. An airplane having, in combination, a

steering rudder, a pair of right and left air resistance braking surfaces, and means providing for the operation of both surfaces air stream; each auxiliary surface havin an movement; said rudder connection having a compensating device to allow rudder movement after limit movement of either auxiliary surface.

' JOSEPH BLONDIN.

to set them against the air simultaneously without effect on the rudder and connecting them thereto.

6. An airplane having, in combination, a rudder, a pair of right and left hand air resistance braking surfaces which are operatively attached to respective dihedral wing struts of the airplane, and selective operating means connecting the brake surfaces and the rudder for concurrently producing right rudder or left rudder and respective action of the relative brake surface and for actuating the said surfaces without action of the rudder, and means on the struts for stopping the free brake surfaces in the bed of the wind.

7 An airplane having rudder, aileron and elevator surfaces, and supplemental brake,

rudder and quasi-aileron means consisting of a set of right and left auxiliarycontrol surfaces mounted on dihedral struts, and means for operating said auxiliaries upward together as brakes and spoilers, or to operate either as down-effect ailerons and also with rudder effect while the other drags idle in the 

